I've been working with W.F. Smith for thirty years and I've never had any problems. They've always been very helpful, in fact I would say extremely so. The were here most recently in the fall to do a checkup for the winter. They come twice a year and I have a contract with them. The prices are comparable to others. They may be slightly higher than one or two others I've called, but they're very reliable and they're the ones who originally put my system in, so I've stuck with them.